Hi ianmcnll.

Bear with me for a moment and I will try explain this a different way that might be clearer.

Remember the sound engine is what drives the entire sound a keyboard produces regardless of make and model.

Now forget accessibility for you the end user for a moment. Even if KORG hid away all these advanced features from the end user and only used them themselves for making the factory sounds, the sound engine is infinitely more advanced than the competition so these guys can make it produce sounds no other keyboard can.

Why... because KETRON and every other arranger keyboard simply dosen't have a sound engine that can do that, so regardless of what level the sound designer is at. They simply don't have the tools to do what a KORG sound designer has access to.

So even if you will never use the sound engine to make your own sounds, the mere fact that the sound designers working for KORG had a sound engine that deep to work with in the first place means the factory presents will contain some pretty excising stuff that is simply impossible for another make of arranger keyboard to produce.

In short, regardless if you use the sound engine or not to make your own sounds, it's responsible for everything the keyboard produces and because it's so advanced, it can do things no other arranger can and that's what the KORG programmers will give you in the form of factory presets.

So even if you don't use it yourself, KORG did to produce the factory sounds.

Regards
James